2,3-Oxidosqualene
Encyclopedia
2,3- Oxidosqualene ((S)-2,3-epoxysqualene) is an intermediate in the synthesis of the membrane sterol precursors lanosterol
and cycloartenol
, as well as saponin
s. It is formed from squalene
by squalene monooxygenase
. 2,3 oxidosqualene is the substrate
of various oxidosqualene cyclases, including lanosterol synthase
, which produces lanosterol
, a precursor to cholesterol.
2,3-(R) Oxidosqualene is an inhibitor of lanosterol synthase.
Lanosterol
Lanosterol is a tetracyclic triterpenoid, which is the compound from which all steroids are derived.-Role in creation of steroids:Elaboration of lanosterol under enzyme catalysis leads to the core structure of steroids. 14-Demethylation of lanosterol by CYP51 eventually yields...
and cycloartenol
Cycloartenol
Cycloartenol is an important type of stanol found in plants. The biosynthesis of cycloartenol starts from the triterpenoid squalene. It is the first precursor in the biosynthesis of other stanols and sterols, referred to as phytostanols and phytosterols in photosynthetic organisms and plants...
, as well as saponin
Saponin
Saponins are a class of chemical compounds, one of many secondary metabolites found in natural sources, with saponins found in particular abundance in various plant species...
s. It is formed from squalene
Squalene
Squalene is a natural organic compound originally obtained for commercial purposes primarily from shark liver oil, though plant sources are used as well, including amaranth seed, rice bran, wheat germ, and olives. All plants and animals produce squalene, including humans...
by squalene monooxygenase
Squalene monooxygenase
Squalene monooxygenase is an enzyme that uses NADPH and molecular oxygen to oxidize squalene to 2,3-oxidosqualene . Squalene epoxidase catalyzes the first oxygenation step in sterol biosynthesis and is thought to be one of the rate-limiting enzymes in this pathway...
. 2,3 oxidosqualene is the substrate
Substrate (biochemistry)
In biochemistry, a substrate is a molecule upon which an enzyme acts. Enzymes catalyze chemical reactions involving the substrate. In the case of a single substrate, the substrate binds with the enzyme active site, and an enzyme-substrate complex is formed. The substrate is transformed into one or...
of various oxidosqualene cyclases, including lanosterol synthase
Lanosterol synthase
Lanosterol synthase is an oxidosqualene cyclase enzyme that converts -2,3-oxidosqualene to a protosterol cation and finally to lanosterol. Lanosterol is a key four-ringed intermediate in cholesterol biosynthesis...
, which produces lanosterol
Lanosterol
Lanosterol is a tetracyclic triterpenoid, which is the compound from which all steroids are derived.-Role in creation of steroids:Elaboration of lanosterol under enzyme catalysis leads to the core structure of steroids. 14-Demethylation of lanosterol by CYP51 eventually yields...
, a precursor to cholesterol.
2,3-(R) Oxidosqualene is an inhibitor of lanosterol synthase.